G.W. Wong¹, A.M. Ali² and H.F. Sew^1*

¹Immunology Unit, Department of Clinical Laboratory Science, Faculty of Medicine and Health Sciences,
Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
²Department of Biotechnology, Faculty of Food Science and Biotechnology, Universiti Putra Malaysia
3400 Serdang, Selangor, Malaysia

(Received 23 March 1999 /Accepted 15 August 1999)

Abstract.
Human IL-18 cDNA which was amplified via the reverse transcription polymerase chain reaction of total RNA isolated from KU812F, a chronic myelogenous leukemic cell line, was successfully cloned into pTrcHis-2TOPO vector and expressed in E. coli. The authenticity of the human IL-18 cDNA sequence was confirmed by DNA sequencing. It exhibited 100% identity to the human IL-18 cDNA sequence as published in the database Genbank (accession no. D49950). SDS PAGE analysis of the crude lysates from pTrcHis TOPO.1L-18 cultures induced with I mM IPTG yielded a prominent protein band of the expected molecular mass of approximately 23kDa. The expressed recombinant protein was purified from the soluble fraction using the Talon metal affinity resin. A human T cell line, CEM-SS and PBMC were shown to exhibit constitutive basal levels of IL-18 mRNA expression. Con A and PMA upregulated IL-18 mRNA expression in CEM SS. Dibutyryl cyclic AMP and dexamethasone were found to downregulate IL-18 mRNA synthesis in PBMC.

Keywords: 11,18, cloning, expression, pTrcHis2 TOPO

M. Maizan, A.R. Mohd. Ali and S.H. Sharifah*

Veterinary Research Institute, 59, Jalan Sultan Golan Shah 31400, Ipoh Perak

Received 28 August 2000 / Accepted 12 December 2000

Abstract.
A cytopathogenic infectious agent isolated from the lungs of dead and sick pigs with severe pneumonia during the 1998/1999 Nipah virus outbreak was used for the development of a RT-PCR, for the rapid diagnosis of Nipah virus infection. Oligonucleotide primers were constructed and reverse transcriptase polymerase chain reaction (RT-PCR) and nested PCR were established for the detection of Nipah and Hendra viruses. The primary and nested PCR based on the primers of specific regions within the N genes of both viruses amplified a 397 bp and a 300 bp product respectively. The nucleotide sequence of the amplified 397 bp fragments of the 1998 pig isolate and the naturally occurring Nipah virus from the buffy coat of blood of pigs from a recently identified farm was compared with the published N gene sequences of the Nipah and Hendra viruses. The sequences of the 397 bp PCR product derived from tissue culture infected cells and buffy coats showed 99% and 70.8% homology with Nipah and Hendra virus respectively. The amplified products were further identified as Hendra or Nipah virus by restriction enzyme analysis using EcoRV.

Keywords: Nipah virus, RT PCR, sequencing, restriction enzyme analysis

J. Hamed, M.A. Hassan^*,1Y Shirai, A. Ariff
and M.I.A. Karim

Department of Biotechnology, Faculty of Food Science and Biotechnology,
University Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
¹Department of Biochemical Engineering and Science, Faculty of Computer Science and Systems Engineering,
Kyushu Institute of Technology, Iizuka, Fukuoka 820 8502, Japan

Received 3 January 2000 / Accepted 5 July 2000

Abstract.
Leachates from municipal solid wastes (MSW) in Kuala Lumpur area were subjected to anaerobic treatment under specified conditions for the production of short chained organic acids. Two different leachate samples were used in this study; fresh leachate from the city council garbage trucks and combined leachate taken from several cells at the sanitary landfill. The objective is to evaluate the effect of pH and inoculum on organic acids production during anaerobic treatment of leachate from MSW. Treatments were carried out at 30^oC for 7 10 days under different conditions of pH such as uncontrolled pH, adjusted to initial pH 7, controlled at pH 7 for 24 h, and continuous control at pH 5.5 and pH 7. The production of organic acids from fresh leachate was highest when the pH was adjusted initially to pH 7 with no further pH control. About 45 g/L total organic acids was produced after five days of treatment, with 28 g/L lactic acid, 8 g/L acetic acid and 9 g/L propionic acid. Based on the initial BOD, the organic acid yield was about 80%. In contrast, with the combined landfill leachate the highest organic acids production obtained was only 14 g/L when the pH was controlled at pH 5.5, with acetic acid as the main product. Lower pHs appeared to increase organic acids production in the combined landfill leachate. When the fresh leachate was autoclaved and seeded with 10% fermented kitchen garbage, the highest organic acids achieved were between 34 37 g/L. The highest selectivity of lactic acid (85%) was achieved during treatment of fresh leachate seeded with kitchen garbage without any pH adjustment. Overall, our results showed that the fresh leachate could be effectively converted to 45 g/L total organic acids by anaerobic treatment when the initial pH was adjusted to pH 7.

Keywords: Organic acids, municipal solid waste, landfill leachate

A.B. Mandal*, A. Maid and R. Elanchezhian

Biotechnology Laboratory, Central Agricultural Research Institute, Post Box No. 181, Port Blair, 744101, Andaman and Nicobar Islands, India

Received 10 December 1999 / Accepted I1 June 2000

Abstract.
In vitro flowering in maize (Zea mays L) was observed on MS medium supplemented with 4 mg L ^-1 BAP (6 Benzyl amino purine) and 0.5 mg L ^-1 NAA (Naphthalene acetic acid). The flowering was induced under 16/8 h light/ dark regime at 25±2^oC, suggesting a long day requirement to facilitate flowering in this crop. However, only female flowers were produced, indicating compatibility of the aforementioned dose of BAP and NAA in promoting female flower induction. The level of auxin and cytokinin may be further manipulated to obtain male flowers which is essential to perform in vitro fertilization.

Keywords: In vitro flowering, maize, growth regulators